.filter {
    position: relative;
    z-index: 3;
    height: 40px;

    .mask {
        position: fixed;
        z-index: 2;
        left: 0;
        right: 0;
        top: 0;
        bottom: 0;
        background-color: rgba(0, 0, 0, 0.5);
    }

    .content {
        position: absolute;
        z-index: 3;
        width: 100%;
        background-color: #fff;
    }
}
